A short and efficient total synthesis of (+)-chinensiolide B is reported, starting from commercially available α-santonin. This strategy could be used for rapid preparation of chinensiolides and their derivative for further structure activity relationship studies.

A series of isochromans were oxidized and brominated by using 1.2 equiv of CuBr2 in CH3CN at reflux to give the corresponding bromo benzaldehydes in moderate yields. A plausible mechanism for this transformation has been suggested.

A formal synthesis of (−)-platensimycin has been successfully carried out using a tandem C–H oxidation/C–C coupling (cyclization)/rearrangement as the key step.